TL;DR: This is a family program and drinking and smoking is not permitted at the sight. Showing up sober is recommended. If you are planning on getting intoxicated prior to the tour being stoned is recommended over being drunk.
This tour takes place at a public trail head operated by Boulder Open Space and Mountain Parks (OSMP) as such it is subject to their rules and regulations which regarding drinking and smoking are quoted here:
Consumption and open containers of alcohol are prohibited on Open Space and Mountain Parks. Marijuana consumption is prohibited in public, including on OSMP. City ordinance prohibits smoking on OSMP (including the use of electronic smoking devices). Glass containers are prohibited on OSMP land. - https://bouldercolorado.gov/osmp-rules-and-regulations
If you plan on doing an activity prior to the tour that might involve you coming to the tour intoxicated be safe. You can get an Uber/lyft to the tour. I will offer my experiences if they help you make your choices: The tour covers astrophysics which can be hard to understand even with a sober mind. People that have come drunk have said they regretted it and get less from the tour. On the other hand people that have come under the influence of marijuana enjoy it more than people that come drunk. where I still feel like being stoned hinders the ability to understand the astrophysical concepts we cover it seems to open the mind up to being able to be amazed by the little things. So while being stoned you might not understand as much what you do understand might seem more impactful.
Anyone that is inebriated to the point of bothering other guests will be asked to leave. This is a family program and intoxication is out of the norm. If you are unable to be mature and respectful we reserve the right to ask you to leave.
Honestly I think the night sky especially in Colorado doesn’t need any enhancement to be awe inspiring so I would always recommend sobriety.
If you or a loved one is having issues with drug use I recommend visiting the Harm Reduction Action Center https://www.harmreductionactioncenter.org/ They have information and facilities for safer drug use and rehabilitation.